1. Field of the Invention
This invention relates to a pulsed corona discharge apparatus to remediate a contaminated fluent material. More particularly, the fluent material is passed through a reactor vessel having a plurality of electrically interconnected wire electrodes each circumscribed by a second electrode. A high voltage pulse to the wire electrodes generates a streamer corona discharge that breaks down the contaminants in the fluent material to more innocuous constituents.
2. Background of the Invention
Fluent materials, typically gases, but also including liquids, are frequently contaminated with hazardous or odiferous materials, such as volatile organic compounds. Before discharging the fluent material to the environment, it is desirable, and may be legally mandated, that the hazardous compounds be remediated by removal or destruction. Methods to remediate hazardous compounds suspended within a fluent material include high temperature thermal incineration, catalytic incineration and absorption utilizing materials such as activated carbon. These methods tend to be expensive and have a low through-put.
Another approach is to break down the hazardous compounds into innocuous materials, such as water and carbon dioxide, by reacting the hazardous compounds with a stream of high energy electrons generated by a partial electrical breakdown of the fluent material. This method is disclosed in U.S. Pat. No. 5,236,672 to Nunez et al. and in U.S. Pat. No. 5,490,973 to Grothaus et al. Both the Nunez et al. and the Grothaus et al. patents are incorporated by reference in their entireties herein.
The Grothaus et al. patent discloses a reactor having a wire electrode that extends along a longitudinal axis of a tubular electrode circumscribing the wire electrode. Insulators at the entrance and exit of the tubular electrodes center the wire electrode along the axis of the tubular electrode, provide tension to the wire electrode to prevent sagging, electrically isolate the wire electrode from the tubular electrode, and provide a gas seal to prevent the flow of gas to parts of the reactor other than the tubular electrode. The insulators are baffled to allow for the ingress and egress of the fluent material and gases are introduced into each reactor tube separately. As a result, complicated gas seals are required, the through-put is low and the number of machine parts required is high.
In addition, the Grothaus et al. patent discloses a method of control of the high voltage power supply that does not detect improper high voltage discharges and so may lead to a failure to remediate the hazardous gas and to possible destruction of the reactor itself.
There remains a need for a pulsed corona discharge apparatus suitable to remediate a contaminated fluent material that does not have the disadvantages of the prior art discussed hereinabove.